1. Field of the Invention
The present invention relates to network interface devices. More specifically, the present invention relates to interrupt control and monitoring systems in a host adapter of a network interface.
2. Description of the Related Art
Personal computers (PC's) such as microcomputers have gained widespread use in recent years primarily because they are inexpensive and yet powerful enough to handle computationally-intensive user applications. Data storage and data sharing functions of personal computers are often expanded by coupling a group of such computers to peripheral devices such as disk drives, tape drives, and printers. The peripheral devices and the personal computers are interconnected through a single communications network, such as a local area network.
The group of computers is coupled using interfaces that facilitate and accelerate communications among the computers and peripheral devices. A host adapter is a common interface device that is used to connect a first bus that has a specified protocol for transferring information over the first bus and a first data transfer speed to a second bus. The second bus also has a specified protocol for transferring information over the second bus at a second data transfer speed. The host adapter operates to transfer information between the first bus and the second bus.
The host adapter performs numerous functions to facilitate communications among devices. One function that may be supported by the host adapter is interrupt control and monitoring. Host adapter hardware and software communicate by issuing interrupts indicating command completion, error reporting, and driver intervention.
Although interfaces are have high-speed capabilities for transferring information, access to control and status information is hindered when the control and status information to be accessed is on an opposite side of a bus from the accessing device or controlling software driver. What is needed is an efficient way of posting interrupts to utilize a host driver, reduce bus read accesses, and reduce interference with normal operations of the host adapter.